This invention relates to new and useful improvements in air-oil flooded screw compressor systems, and method.
In U.S. Pat. No. 3,785,755, an oil flooded screw compressor system separates the air and oil and then cools the air to extract moisture therefrom. The cooled air and hot oil are then passed through a heat exchanger which heats the air for use and cools the oil to a desired temperature for recirculation through the compressor. The output air is discharged from the heat exchanger at about 160 degrees F., at about 100 psi, and at about 25 percent relative humidity. In general, users of compressed air prefer the air to be substantially moisture free. For this purpose, drying and regenerating towers are employed in the above and other systems through which the output air is directed. Since a portion of the output air is used to regenerate its dryers, the moisture laden condition of these prior systems requires them to use approximately 15% percent of the output energy for purging. The purging energy is of course lost as far as ultimate use is concerned, and it is desired that this loss of energy be kept as low as possible.